Scientists have found evidence of the seasons on the surface of Saturn's moon, Titan, due to observations similar to the sunlight that reflects the spots on the earth.
We already know that Titan experienced methane rains on the southern pole, making it the only astronomical object we know where it rains on the surface. The Moon tilts on its axis, but as its position changes, and as the clouds refused to form over the northern pole, scientists wondered if and when they would see evidence of changing seasons. Cassini's long-awaited rainfall eventually came on June 7, 2016, signing the beginning of Titan's polar north wind.
"Everyone was confused why not," said Gizmodo Rajani Dhingra, a physics student at the University of Idaho. "This tells us that not only is it happening, it was delayed."
Seasons should work similarly on Titanium on Earth, as both bodies lean on their rotating axes. The hemisphere facing the sun lives "summer," while the hemisphere is leaning towards the sun. "When the Cassini mission reached Saturn in 2004, Titan's southern hemisphere faces the summer, and spacecraft recorded evidence of moon rainfall in the southern polar region.
There are about 14 years between Titan's solstice or times that each pole receives the most sun. (On Earth, of course, the solstice is only six months.) So, as Titan's southern summer ended and started north in the summer, the researchers expected to observe clouds and rain in the northern hemisphere. But the rain will not come.
Today, scientists report the results of an analysis of data from a Cassini spectrometer: a distinct bright spot covering an area of Pennsylvania size or 120,000 square kilometers, but only on certain days. Researchers have hypothesized that they have seen the liquid fill in the cracks on the surface of the moon, causing it to reflect more sun. In other words, they saw a large wet surface on the surface, like a large dump of wet pavements – the result of the rain.
It is important to note that there are other hypotheses about what would have caused the enlightened face, such as fog, according to the newspaper published in Geophysical Research Letters.
Researchers felt, based on their analysis, that wetting the surface from the alleged rain was still the most likely explanation, which would make it the first observation of the rain on Titan's northern pole. This "wet passage effect" could now serve as a new way to observe this rain.
And now that the researchers have seen evidence of rain, they hope to understand why she was so late. "This is a great puzzle piece," Dhingra said Gizmodo. "This observation will help us understand what has happened." Perhaps it will help scientists understand Titan's geology and the roughness of its surface.
This result is yet another example of important postmachine science in the Cassini mission, which ended in September 2017, when the probe threw itself into Saturn. But scientists hope that more science will come soon – Saturn is now without probes, but NASA has funded a project that would send a quad-copter to Titan's surface.
But the work of Titan's science was a true dream for Dhingra. She said, "Surely, you come to work every day significant."